FIELD OF THE INVENTION
This invention relates to an apparatus for uniformly heating or cooling sand.
More specifically, the invention provides an apparatus for heating or cooling sand comprising a heat exchange section provided in a lower portion thereof with flow regulating means consisting of a pyramidal or conical funnel assembly for causing flow of sand in the heat exchange section over the entire sectional area thereof.
Unlike a liquid, when sand contained in a container is discharged through an outlet provided at the bottom of the container, the sand does not uniformly descend over the entire cross-sectional area of the container but rather, only the sand directly above the outlet falls downwardly, and the rest of sand remains more or less stationary in the container. Regarding this type of movement of sand, there are various descriptions in the literature; for instance, a disclosure about this is contained at page 373 of "Apparatus for Transporting Powdery and Granular Materials" by Takeshi Karino.